Open Metering System (OMS) solution was initiated by associations of meter and communication manufacturers.
The main result of this initiative was the new specification based on current EN 17357 standard which has defined an open, manufacturer independent, interoperable, device and interface specification unifying the communication with electricity, gas, heat and water meters.
OMS ensures that already installed metering equipment can be used or modified for use under the OMS specification.
Wireless M-Bus S and T modes can both be used. The T-mode, with a data rate of 100 Kchips ensures short communication times with lowest consumption while the S mode ensures longer range. The privacy has been secured by the use of strong data encryption.
AES-128 encryption standard has been chosen for the Wireless M-Bus link which ensures privacy for the consumer by preventing unauthorised reading of meter data, securing data integrity for the utility company and protection for energy theft.
M-Bus is an European Standard (EN 13757) for remote reading of gas, electricity and other consumption meters.
It uses only 2 wires which makes it very cost-effective, robust and simple to maintain. It is also used for remote readings of temperature, pressure, fuel consumption and many other sensors.
M-Bus AMR system consists of slave devices (placed on or connected to meters) and a master which reads the data from the slave devices and provides them with power supply by using the same pair of wires. User then reads the data from the central master unit using other communication channels (TCP/IP or similar).
M-Bus is the most popular system for Automatic Meter Reading for several key facts:
Since it uses a pair of wires it is recommended to install the wires during the building construction phase. Installing the wires to connect several buildings or parts of a building after the building construction is complete may be relatively cost-ineffective.
In the implementation scenarios where M-Bus installation is not recommended or unavailable to implement, Wireless M-Bus (EN 13757-4) system is the solution.
It's robustness, very low energy consumption (battery powered) and simplicity in network set-up make it the most popular choice in Wireless AMR systems.
Wireless M-Bus transmitters are battery powered devices mounted directly or next to the metering devices. Transmitters periodically do meter readouts and periodically send the meter readout data to a fixed or a mobile (Walk-By, Drive-By) Wireless M-Bus receivers. Readout data are afterwards sent from receiver to the central server/software location for further data analysis and billing.
Adherence to OMS (Open Metering System) ensures reading compatibility with any Wireless M-Bus equipment manufacturer.
LoRaWAN™ is a communications protocol and architecture that utilizes the LoRa physical layer.
Data rates are within the range from 300bps to 5.5kbps with two high-speed channels at 11 kbps and 50 kbps (FSK modulation). Three classes of devices have been defined to address specific application requirements:
Class A: Each device's uplink transmission is followed by two short downlink receive windows
Class B: In addition to the Class A functionality, Class B devices open extra receive windows at scheduled times
Class C: These devices have a continuous open receive widow except when transmitting LoRaWAN™ has two layers of security:
The network security authenticates the node in the network (Message Integrity Check (MIC)). The application layer of security ensures the network operator does not have access to the application data.